Compounds of the formula ##STR1## wherein R.sup.1 is hydrogen, alkyl of 1 to 6 carbon atoms, or NR.sup.4 R.sup.5, wherein R.sup.4 and R.sup.5 are independently selected from hydrogen and alkyl of 1 to 6 carbon atoms or a pharmaceutically acceptable cation;R.sup.2 is hydrogen, hydroxy, alkanoylamino of 1 to 6 carbon atoms, morpholino, halogen, hydroxyalkyl of 1 to 6 carbon atoms, COOR.sup.6 wherein R.sup.6 is alkyl of 1 to 6 carbon atoms or a pharmaceutically acceptable cation, alkoxy of 1 to 6 carbon atoms, NR.sup.7 R.sup.8 wherein R.sup.7 and R.sup.8 are independently selected from alkyl of 1 to 6 carbon atoms, alkanoyl of 1 to 6 carbon atoms, hydrogen, alkoxy of 1 to 6 carbon atoms, aminoalkyl of 2 to 6 carbon atoms, alkylaminoalkyl wherein each alkyl group is independently selected from alkyl groups having 2 to 6 carbon atoms, and dialkylaminoalkyl wherein each alkyl group is independently selected from alkyl groups having one to six carbon atoms, with the proviso that only one of R.sup.7 and R.sup.8 may be alkoxy; andR.sup.3 is hydrogen, alkyl of 1 to 6 carbon atoms, phenyl or substituted phenyl wherein the phenyl group may be substituted with one or two substituents selected from the group consisting of alkyl of 1 to 6 carbon atoms, nitro, amino, halogen, (e.g., fluoro, chloro, bromo, or iodo), haloalkyl of 1 or 2 carbon atoms and up to 5 halogen atoms (e.g., fluoro, chloro, bromo or iodo), hydroxyl, or alkoxy of 1 to 6 atoms and pharmaceutically acceptable acid addition salts thereof. The compounds have antibacterial activity.

Claim:

I claim:

1. A compound of the formula ##STR6## wherein R.sup.1 is hydrogen, alkyl of 1 to 6 carbon atoms, or NR.sup.4 R.sup.5, wherein R.sup.4 and R.sup.5 are independently selected from hydrogenand alkyl of 1 to 6 carbon atoms or a pharmaceutically acceptable cation;

R.sup.2 is hydrogen, hydroxy, alkanoylamino of 1 to 6 carbon atoms, morpholino, halogen, hydroxyalkyl of 1 to 6 carbon atoms, COOR.sup.6 wherein R.sup.6 is alkyl of 1 to 6 carbon atoms or a pharmaceutically acceptable cation, alkoxy of 1 to 6carbon atoms, NR.sup.7 R.sup.8 wherein R.sup.7 and R.sup.8 are independently selected from alkyl of 1 to 6 carbon atoms, alkanoyl of 1 to 6 carbon atoms, hydrogen, alkoxy of 1 to 6 carbon atoms, aminoalkyl of 2 to 6 carbon atoms, alkylaminoalkyl whereineach alkyl group is independently selected from alkyl groups having 2 to 6 carbon atoms, and dialkylaminoalkyl wherein each alkyl group is independently selected from alkyl groups having one to six carbon atoms, with the proviso that only one of R.sup.7and R.sup.8 may be alkoxy; and

R.sup.3 is hydrogen, alkyl of 1 to 6 carbon atoms, phenyl or substituted phenyl wherein the phenyl group may be substituted with one or two substituents selected from the group consisting of alkyl of 1 to 6 carbon atoms, nitro, amino, halogen,haloalkyl of 1 or 2 carbon atoms and up to 5 halogen atoms, hydroxyl, or alkoxy of 1 to 6 atoms and pharmaceutically acceptable acid addition salts thereof.

18. A method according to claim 16, wherein R.sup.1 is hydrogen, a pharmaceutically acceptable cation or amino.

19. A method according to claim 16, wherein R.sup.2 is hydrogen, amino or hydroxy and R.sup.3 is hydrogen or phenyl.

20. A method according to claim 19, wherein R.sup.1 is hydrogen, a pharmaceutically acceptable cation or amino.

Description:

BACKGROUND OF THE INVENTION

This invention relates to azetidinyl quinolone carboxylic acids and esters, antibacterial compositions containing said compounds, methods of using said compounds, and methods of preparing said compounds.

U.S. Pat. No. 4,563,459 refers to 1-cyclopropyl-1,4-dihydro-4-oxo-quinoline carboxylic acids wherein the moiety in the 6-position is hydrogen, fluorine, chlorine, bromine or nitro and the moiety in the 7-position is hydrogen, chlorine, fluorineor NR.sup.3 R.sup.4 wherein R.sup.3 and R.sup.4 represent separate groups or, together with the nitrogen atom on which they are positioned, may form a 5-membered or 6-membered heterocyclic ring.

Japanese Kokai SHO 60-89480 refers to compounds of the formula ##STR2## wherein Z is nitrogen or CH; X is halogen; R.sup.1 and R.sup.2 are hydrogen, acyl or lower alkyl;

m is 1 or 2; and n is 1, 2 or 3. However, no specific quinoline compounds are disclosed.

SUMMARY OF THE INVENTION

The present invention relates to compounds of the formula ##STR3## wherein R.sup.1 is hydrogen, alkyl of 1 to 6 carbon atoms, or NR.sup.4 R.sup.5 wherein R.sup.4 and R.sup.5 are independently selected from hydrogen and alkyl of 1 to 6 carbonatoms or a pharmaceutically acceptable cation;

R.sup.2 is hydrogen, hydroxy, alkanoylamino of 1 to 6 carbon atoms, morpholino, halogen, hydroxyalkyl of 1 to 6 carbon atoms, COOR.sup.6 wherein R.sup.6 is alkyl of 1 to 6 carbon atoms or a pharmaceutically acceptable cation, alkoxy of 1 to 6carbon atoms, NR.sup.7 R.sup.8 wherein R.sup.7 and R.sup.8 are independently selected from alkyl of 1 to 6 carbon atoms, alkanoyl of 1 to 6 carbon atoms, hydrogen, alkoxy of 1 to 6 carbon atoms, aminoalkyl of 2 to 6 carbon atoms, alkylaminoalkyl whereineach alkyl group is independently selected from alkyl groups having 2 to 6 carbon atoms, and dialkylaminoalkyl wherein each alkyl group is independently selected from alkyl groups having one to six carbon atoms, with the proviso that only one of R.sup.7and R.sup.8 may be alkoxy; and

R.sup.3 is hydrogen, alkyl of 1 to 6 carbon atoms, phenyl or substituted phenyl wherein the phenyl group may be substituted with one or two substituents selected from the group consisting of alkyl of 1 to 6 carbon atoms, nitro, amino, halogen(e.g., fluoro, chloro, bromo, or iodo), haloalkyl of 1 or 2 carbon atoms and up to 5 halogen atoms (e.g., fluoro, chloro, bromo or iodo), hydroxyl, or alkoxy of 1 to 6 atoms and pharmaceutically acceptable acid addition salts thereof. The compounds haveantibacterial activity.

The present invention also relates to pharmaceutical compositions comprising a pharmaceutically acceptable carrier or diluent and a compound of the formula I or a pharmacutically acceptable salt thereof in an antibacterially effective amount. The present invention also provides a method of treating an animal, including a human being, having a bacterial disease which comprises administering to the animal (e.g., mammal, bird or fish) an antibacterially effective amount of a compound of theformula I or a pharmaceutically acceptable acid addition salt thereof. The present invention also relates to methods of preparing the compounds of formula I.

The compounds of the invention include racemic mixtures and optical isomers. Preferred compounds of the invention are those of formula I wherein R.sup.1 is hydrogen, a pharmaceutically acceptable cation (e.g., sodium or potassium), or amino. Other preferred compounds are those of formula I wherein R.sup.2 is hydrogen, amino, hydroxy, hydroxymethyl, acetylamino or COOR.sup.6, wherein R.sup.6 is hydrogen, a pharmaceutically acceptable cation, or amino. Other preferred compounds are those offormula I wherein R.sup.3 is hydrogen or phenyl. More preferred compounds are those wherein R.sup.1 is hydrogen, a pharmaceutically acceptable cation, or amino; R.sup.2 is hydrogen, amino, or hydroxy and R.sup.3 is hydrogen or phenyl. Specificpreferred compounds are as follows:

The compounds of the present invention may be prepared by reacting a quinolone of the formula ##STR4## wherein R.sup.1 is as defined above and X is fluoro, chloro, bromo or iodo (preferably, fluoro or chloro; more preferably, fluoro) with anamine of the formula ##STR5## wherein R.sup.2 and R.sup.3 are as defined above, in an inert solvent or in a basic solvent. Examples of suitable solvents are tetrahydrofuran, pyridine, ethanol, chloroform, dimethylsulfoxide, dimethylformamide, water andmixtures thereof. If the solvent is not a basic solvent such as, for example, pyridine, it is desirable to add a base to the reaction mixture. The base serves to facilitate completion of the reaction by reacting with the hydrogen fluoride that isproduced in the reaction. The addition of DBU (which is a strong base) to the reaction mixture is preferred. A preferred solvent is a mixture of acetonitrile and 1,8-diazabicyclo(5.4.0) - undec.-7-ene(DBU). Especially preferred, is acetonitrilesolvent containing 1 to 3 equivalents of DBU. The temperature and pressure are not critical. Generally, however, a temperature of 30 to 100.degree. C. and a pressure of 0.5 to 2 atmospheres are preferred. More preferably, the pressure is ambientpressure (generally, about 1 atmosphere). Although a significant amount of product may be formed in about 5 minutes, the reaction is generally allowed to proceed overnight. The product is isolated by conventional methods. For example, the product maybe isolated by adding water to the reaction mixture, adjusting the pH to 7.0-7.4, collecting the resulting precipitate by filtration and then water washing and drying the precipitate. Using conventional methods, compounds of the present inventionwherein R.sup.1 is other than hydrogen may be prepared by converting a compound of the formula I wherein R.sup.1 is hydrogen to the corresponding ester or amide. Alternatively, a compound of the formula II wherein R.sup.1 is hydrogen may be converted tothe corresponding ester or amide by conventional methods and that ester or amide may then be used to prepare a compound of the formula I as described above.

Compounds of the formula II may be prepared as described in U.S. Pat. No. 4,563,459.

The pharmaceutically acceptable acid addition salts of the compounds of the formula I are prepared in a conventional manner by treating a solution or suspension of the free base of the formula I with about one chemical equivalent of apharmaceutically acceptable acid. Conventional concentration and recrystallization techniques are employed in isolating the salts. Illustrative of suitable acids are acetic, lactic, succinic, maleic, tartaric, citric, gluconic, ascorbic, benzoic,methanesulfonic, cinnamic, fumaric, phosphonic, hydrochloric, hydrobromic, hydroidic, sulfamic and sulfonic acid.

The pharmaceutically acceptable cationic salts of formula I may be prepared by conventional methods from the corresponding acids, e.g., by reaction with about one equimolar amount of a base. Examples of suitable cationic salts are those ofalkali metals such as sodium or potassium, alkaline earth metals such as magnesium or calcium, and ammonium or organic amines such as diethanol amine or N-methyl-glucamine.

The compounds of formula I and the pharmaceutically acceptable acid addition salts thereof are broad spectrum antibacterials useful in the treatment of bacterial infections, particularly the treatment of infections of gram-positive bacterialstrains.

The compounds of the present invention may be administered alone, but will generally be administered in admixture with a pharmaceutical carrier selected with regard to the intended route of administration and standard pharmaceutical practice. For example, they can be administered orally or in the form of tablets containing such excipients as starch or lactose, or in capsules either alone or in admixture with excipients, or in the form of elixirs or suspensions containing flavoring or coloringagents. In the case of animals (for example, swine, cattle, horses, and poultry), they are advantageously contained in an animal feed or drinking water in a concentration of about 5 to about 5000 ppm, preferably about 25 to about 500 ppm. They can beinjected parenterally, for example, intramuscularly, intravenously or subcutaneously. For parenteral administration, they are best used in the form of a sterile aqueous solution which can contain other solutes, for example, enough salt or glucose tomake the solution isotonic. In the case of animals, compounds can be administered intramuscularly or subcutaneously at dosage levels of about 0.1 to about 50 mg/kg/day, advantageously about 0.2 to about 10 mg/kg/day, given in a single daily dose or upto 3 divided doses.

The invention also provides pharmaceutical compositions comprising an antibacterially effective amount of a compound of the formula I or a pharmaceutically acceptable acid addition salt thereof together with a pharmaceutically acceptable diluentor carrier.

The compounds of the present invention can be administered to humans for the treatment of bacterial diseases by either the oral or parenteral routes, and may be administered orally at dosage levels of about 0.1 to about 500 mg/kg/day,advantageously about 0.5 to about 50 mg/kg/day, given in a single dose or up to 3 divided doses. For intramuscular or intravenous administration, dosage levels are about 0.1 to about 200 mg/kg/day, advantageously about 0.5 to about 50 mg/kg/day. Intramuscular administration may be accomplished with a single dose or up to 3 divided doses. Intravenous administration may be accomplished with a continuous drip. Variations will necessarily occur depending on the weight and condition of the subjectbeing treated and the particular route of administration chosen as will be known to those skilled in the art.

The antibacterial activity of the compounds of the invention is shown by testing according to the Steer's replicator technique which is a standard in vitro bacterial testing method described by E. Steers et al., Antibiotics and Chemotherapy, 9,307 (1959).

The following non-limiting Examples illustrate the invention. All melting points referred to in the Examples are uncorrected.

A mixture of 3-amino-1-azetidine (80 mg, 0.048 mmole), 1-cyclopropyl-6,7-difluoro-1,4-dihydro-4-oxo-quinoline-3-carboxylic acid (10.6 mg, 0.04 mole) and DBU (0.0113 ml, 12.1 mg, 0.08 mmole) in 5 ml of acetonitrile was refluxed under nitrogen(79.degree.-80.degree. C.) for 3 hours and was then allowed to stand at room temperature under nitrogen overnight. The reaction mixture was then filtered and the wet cake was washed with acetonitrile and then with ethyl ether. The cake was then driedin vacuo to give 15 mg of the title compound, m.p. 277.degree.-278.degree. C.

A mixture of 1-cyclopropyl-6,7-difluoro-1,4-dihydro-4-oxo-quinoline-3-carboxylic acid (132.5 mg, 0.005 mmole), azetidine-3-carboxylic acid (55.6 mg, 0.055 mmole) and DBU (0.075 ml, 0.05 mmole) in 5 ml of acetonitrile was refluxed under nitrogenfor 2 hours. The reaction mixture was then allowed to cool at room temperature for 2 hours. The resulting solid was suspended in 3 ml of water and the pH was adjusted to 8.5 by the addition of saturated aqueous NaHCO.sub.3 solution. Ethyl ether wasthen added. The resulting mixture was shaken in a separatory funnel and the organic layer was separated. The aqueous layer was filtered and the filtered solution was freeze dried overnight to yield 180 mg (92%) of the title compound as the disodiumsalt, m.p. 287.degree.-289.degree. C. (dec.).

A mixture of 3-acetylamino-1-azetidine (110 mg, 0.963 mmole), 1-cyclopropyl-6,7-difluoro-1,4-dihydro-4-oxo-quinoline-3-carboxylic acid (212 mg, 0.8 mmole) and DBU (0.134 ml, 137 mg, 0.9 mmole) in 10 ml of acetonitrile were refluxed under nitrogen(79.degree.-80.degree. C.) for one hour and was then allowed to stand at room temperature under nitrogen overnight. The reaction mixture was then filtered and the wet cake was washed with acetonitrile and then with ethyl ether. The cake was then driedin vacuo to give 311 mg of the title compound.

The hydrochloride salt was prepared by adding the title compound (100 mg) to methanolic HCl containing an equivalent amount of HCl and stirring at room temperature for 30 minutes. The solid material that formed was filtered, washed withacetonitrile, and dried in vacuo to give 83.7 mg (76%) of the hydrochloride salt, m.p. 265.degree.-266.degree. C. dec.

A mixture of 3-hydroxymethyl-1-azetidine 4.4 mg, 0.05 mmole), 1-cyclopropyl-6,7-difluoro-1,4-dihydro-4-oxo-quinoline-3-carboxylic acid (10.6 mg, 0.04 mmole) and DBU (0.0113 ml, 12.1 mg, 0.08 mmole) in 5 ml of acetonitrile was refluxed undernitrogen for 3 hours and was then allowed to stand at room temperature under nitrogen overnight. The reaction mixture was then filtered, and the wet cake was washed with acetonitrile and dried in vacuo to give 9.9 mg (59%) of the title compound, m.p. about 300.degree. C.